LXR linux/include/linux/netpoll.h

   1/*
   2 * Common code for low-level network console, dump, and debugger code
   3 *
   4 * Derived from netconsole, kgdb-over-ethernet, and netdump patches
   5 */
   6
   7#ifndef _LINUX_NETPOLL_H
   8#define _LINUX_NETPOLL_H
   9
  10#include <linux/netdevice.h>
  11#include <linux/interrupt.h>
  12#include <linux/rcupdate.h>
  13#include <linux/list.h>
  14
  15union inet_addr {
  16        __u32           all[4];
  17        __be32          ip;
  18        __be32          ip6[4];
  19        struct in_addr  in;
  20        struct in6_addr in6;
  21};
  22
  23struct netpoll {
  24        struct net_device *dev;
  25        char dev_name[IFNAMSIZ];
  26        const char *name;
  27        void (*rx_hook)(struct netpoll *, int, char *, int);
  28
  29        union inet_addr local_ip, remote_ip;
  30        bool ipv6;
  31        u16 local_port, remote_port;
  32        u8 remote_mac[ETH_ALEN];
  33
  34        struct list_head rx; /* rx_np list element */
  35        struct work_struct cleanup_work;
  36};
  37
  38struct netpoll_info {
  39        atomic_t refcnt;
  40
  41        unsigned long rx_flags;
  42        spinlock_t rx_lock;
  43        struct semaphore dev_lock;
  44        struct list_head rx_np; /* netpolls that registered an rx_hook */
  45
  46        struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */
  47        struct sk_buff_head txq;
  48
  49        struct delayed_work tx_work;
  50
  51        struct netpoll *netpoll;
  52        struct rcu_head rcu;
  53};
  54
  55#ifdef CONFIG_NETPOLL
  56extern void netpoll_rx_disable(struct net_device *dev);
  57extern void netpoll_rx_enable(struct net_device *dev);
  58#else
  59static inline void netpoll_rx_disable(struct net_device *dev) { return; }
  60static inline void netpoll_rx_enable(struct net_device *dev) { return; }
  61#endif
  62
  63void netpoll_send_udp(struct netpoll *np, const char *msg, int len);
  64void netpoll_print_options(struct netpoll *np);
  65int netpoll_parse_options(struct netpoll *np, char *opt);
  66int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp);
  67int netpoll_setup(struct netpoll *np);
  68int netpoll_trap(void);
  69void netpoll_set_trap(int trap);
  70void __netpoll_cleanup(struct netpoll *np);
  71void __netpoll_free_async(struct netpoll *np);
  72void netpoll_cleanup(struct netpoll *np);
  73int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo);
  74void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
  75                             struct net_device *dev);
  76static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
  77{
  78        unsigned long flags;
  79        local_irq_save(flags);
  80        netpoll_send_skb_on_dev(np, skb, np->dev);
  81        local_irq_restore(flags);
  82}
  83
  84
  85
  86#ifdef CONFIG_NETPOLL
  87static inline bool netpoll_rx_on(struct sk_buff *skb)
  88{
  89        struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo);
  90
  91        return npinfo && (!list_empty(&npinfo->rx_np) || npinfo->rx_flags);
  92}
  93
  94static inline bool netpoll_rx(struct sk_buff *skb)
  95{
  96        struct netpoll_info *npinfo;
  97        unsigned long flags;
  98        bool ret = false;
  99
 100        local_irq_save(flags);
 101
 102        if (!netpoll_rx_on(skb))
 103                goto out;
 104
 105        npinfo = rcu_dereference_bh(skb->dev->npinfo);
 106        spin_lock(&npinfo->rx_lock);
 107        /* check rx_flags again with the lock held */
 108        if (npinfo->rx_flags && __netpoll_rx(skb, npinfo))
 109                ret = true;
 110        spin_unlock(&npinfo->rx_lock);
 111
 112out:
 113        local_irq_restore(flags);
 114        return ret;
 115}
 116
 117static inline int netpoll_receive_skb(struct sk_buff *skb)
 118{
 119        if (!list_empty(&skb->dev->napi_list))
 120                return netpoll_rx(skb);
 121        return 0;
 122}
 123
 124static inline void *netpoll_poll_lock(struct napi_struct *napi)
 125{
 126        struct net_device *dev = napi->dev;
 127
 128        if (dev && dev->npinfo) {
 129                spin_lock(&napi->poll_lock);
 130                napi->poll_owner = smp_processor_id();
 131                return napi;
 132        }
 133        return NULL;
 134}
 135
 136static inline void netpoll_poll_unlock(void *have)
 137{
 138        struct napi_struct *napi = have;
 139
 140        if (napi) {
 141                napi->poll_owner = -1;
 142                spin_unlock(&napi->poll_lock);
 143        }
 144}
 145
 146static inline bool netpoll_tx_running(struct net_device *dev)
 147{
 148        return irqs_disabled();
 149}
 150
 151#else
 152static inline bool netpoll_rx(struct sk_buff *skb)
 153{
 154        return false;
 155}
 156static inline bool netpoll_rx_on(struct sk_buff *skb)
 157{
 158        return false;
 159}
 160static inline int netpoll_receive_skb(struct sk_buff *skb)
 161{
 162        return 0;
 163}
 164static inline void *netpoll_poll_lock(struct napi_struct *napi)
 165{
 166        return NULL;
 167}
 168static inline void netpoll_poll_unlock(void *have)
 169{
 170}
 171static inline void netpoll_netdev_init(struct net_device *dev)
 172{
 173}
 174static inline bool netpoll_tx_running(struct net_device *dev)
 175{
 176        return false;
 177}
 178#endif
 179
 180#endif
 181